Pultrusion process to form specially shaped pieces for transforming electric current into diffused heat

ABSTRACT

Process for producing tubular shaped pieces ( 105 ) having a rectangular cross section of low height, to transform electric current into diffused heat, by means of pultrusion, with continuous formation, added to known reinforcing materials such as roving ( 60 ) and mats ( 65 ) of fibreglas, on one broad side of the shaped piece ( 105 ), of one or more parallel nets ( 72, 73 ) of a weft woven ( 80, 81 ) fabric made from a continuous wire ( 77 ) of highly conductive material coated with insulating material ( 78 ), connected at set intervals to devices ( 111, 112 ) of electric sockets incorporated in the plastic material ( 50 ) so that, when the shaped piece ( 105 ) is cut through at the position of the devices ( 111, 112 ) to form electric sockets, and by filling the panels with insulating foam material ( 145 ) oblong panels ( 116 ) are obtained utilizable for innumerable purpose

BACKGROUND OF THE INVENTION

The invention concerns appliances for transforming electric current intodiffused heat.

The pultrusion process is well known, being one that produces parts of acertain shape possessing mechanical characteristics of a high order bypulling the reinforcing materials, known as roving and mats impregnatedwith thermosetting resins, through a draw bench.

The most widely used kinds of roving are glass yarns laid longitudinallyto the shaped parts in order to increase their resistance to bending andpulling forces.

Mats are fibrous felts, laid out in an even manner, to improveinterlaminar adhesion and make the mechanical characteristics of thematerial produced more homogeneous.

The polymeric matrix, consisting of thermosetting resins, may be chosen,according to the use required, from a wide range of resins, such asepoxy and phenolic or others.

The form of the parts produced through a suitable draw bench canobviously be very varied, of a solid or a tubular structure.

The pultruded part can be easily processed, bored and cut with ordinarytools, and can be joined and assembled by glueing, bolting or riveting.Polymerization takes place inside the draw bench by various processes,the most common being application of heat by electric resistances or bygeneration of radiofrequencies.

Purpose of the above invention is to produce pultruded shaped partswhich not only possess the above characteristics but also those ofgenerating diffused heat by transformation of electric current, with agreatly improved performance as will now be explained.

SUMMARY OF THE INVENTION

Subject of the invention is a process for producing shaped parts bypultrusion that transform electric current into diffused heat.

One or more nets, made from a continuous wire of highly conductivematerial coated with material of high insulating capacity, are insertedin a continuous manner in the plastic material, which nets are formed inthe direction of feed of the shaped part conferring electric continuityupon it from beginning to end.

The shaped part is preferably tubular.

Tube section is preferably rectangular, low in height.

Nets are applied to one of the broad sides of the shaped part.

In one type of execution there are two nets side by side.

The two nets can be joined by an intermediate net of insulatingmaterial.

Nets are made of a weft wave material and are added to the knownreinforcing materials such as continuous threads of fibreglass, orroving, and felted pieces of fibreglass, known as mats.

The matrix is of thermosetting resins of unsaturated polyesters, epoxyor phenolic resin.

The nets are put on before or after the resin bath needed forpultrusion.

Added longitudinally to the nets at fixed intervals, incorporated intothe shaped part, are devices for electric sockets with a groove betweenthem lengthwise to the shaped part.

By cutting the shaped part crosswise at the position of said devices,sockets are created for connection to a source of electricity.

In one type of execution these devices consist of a small flat plate ofelectrically conducting material associated to a second small plate alsoof electrically conducting material, with a central channel facingtowards the first plate, the two being associated by rivets or the like.

The socket devices are inserted at the point where the shaped part willbe cut through, thus obtaining oblong panels so that after said cut,each socket device is cut to make two such devices one being integratedinto one panel and the other into the next panel.

The socket devices are placed on the central axis of symmetry of theshaped part or at its sides.

Advantageously there are two nets and the socket devices are placed inpairs, each net being connected to a socket placed at one end of thepanel with a second socket placed at the other end.

Advantageously the panels are connected to electric current by two headsrespectively insertible at the two ends of said panel.

One head has two contacts electrically connected internally at the twochannels in the two sockets and these are at one end of the panel, whilethe second head has two contacts, also at the position of the channelsin the two sockets, these other contacts being at the other end of thepanel and connected by wires to fit a plug for an external electricitysocket.

Foam material is put inside the panel to increase heat insulation sothat the face of the panel opposite to that holding the electricallyconducting nets remains substantially cold, both because of its distancefrom said net and because of the interposing insulation.

The nets are continuous in the shaped part but separated in the variouspreferred lengths, said lengths being connected by the socket devices.At the sides of the nets, laid in one or more units on one face of thetubular shaped part, there are lateral extensions.

The shaped parts, obtained as described, make possible formation ofdifferent objects and structural bodies of innumerable forms andcharacteristics.

For example, the oblong panels associated side by side, with heads attheir ends, can be set up to form self-carrying walls for various uses,one side being cold and the other generating diffused warmth.

Another example is that of an oven for cooking purposes or treatment ofvarious materials with heat emitting sides, formed of a number of panelssuch as those described or of a more powerful kind to create even highertemperatures if needed.

An indoor room can be easily warmed by one or more panels like theabove, wall or ceiling mounted with the heat generating surface towardsthe environment.

The invention offers evident advantages.

In addition to their high mechanical characteristics, these pultrudedparts provide the further advantage of generating diffused heat by meansof electric current.

The rectangular tubular form with electric nets on one of the widersides separated from the other by insulating material, ensures optimumgeneration of diffused heat from one side, the other being almostcompletely cold.

Realization of generators of diffused heat by a long electric lead isgreatly facilitated by the net formed of highly conductive material witha coating of insulation, in loops along successive rows.

Electrical continiuity is in fact assured over the whole of thegenerator at whatever point the cut is made on the continuous body inwhich the net is inserted.

All this greatly facilitates installation in any place and in anystructure as no problems of electrical or heat insulation can arise.

The shaped parts obtainable with this invention not only offer importantadvantages on structures and in environments generally but alsoenormously facilitate preparation of the structures themselvesassociating high structural solidity to generation of heat, for greatestuser comfort.

BRIEF DESCRIPTION OF THE DRAWINGS

Characteristics and purposes of the invention will be made still clearerby the following examples of its execution illustrated bydiagrammatically drawn figures.

FIG. 1 Pultrusion installation for tubular shaped parts suitable forinsertion of two parallel longitudinal metal nets of high electricalconductivity, and for insertion, at fixed intervals, of current devices,perspective.

FIG. 1a Detail view of FIG. 1.

FIG. 2 Detail of a net, plan view.

FIG. 2a Detail view of FIG. 2.

FIG. 3 Detail of a pultruded part, plan view.

FIG. 4 Oblong panel obtained by cutting the shaped part, plan view.

FIG. 5 The panel in FIG. 3, cross section.

FIG. 6 Oblong panel with heads for electrical connections, with twosocket devices for the two nets, placed on the axis of symmetry, seen inperspective.

FIG. 7 As above with socket devices at the side, perspective view.

FIG. 8 Self-carrying wall generator of diffused heat, made byassociation of pultruded vertical oblong tubular panels, perspective.

FIGS. 8a and 8 b Detail views of FIG. 8.

FIG. 9 Oven created by pultruded vertical tubular parts, generators ofheat, perspective.

FIG. 9a Detail view of FIG. 9.

FIG. 10 Room in a house warmed by a set of horizontal pultruded tubularparts, generators of diffused heat, perspective.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The installation 10 comprises a frame 11 for the reinforcing material, astand 21 to support the bath 22 for the matrix 50 of thermosettingresin, a frame 30 to feed in a pair of copper nets 72, 73 withinsulating coating, a frame 40 for the draw bench 41, for a pulling unit42 and for the cutter 45, and the support 47 for the roller surface 48where the cut shaped parts emerge.

The frame 11 comprises a series of reels 56 resting on the surface 12,for feeding in threads of fibreglass 60, known as roving.

Through the rear transmission formed of pulleys 13 on the shaft 14supported by the rear ends of the frame 15 and the front transmissionformed of a roller 18 supported by the front brackets 17, said rovingconnects with the fibreglass felt mat 65 fed in off the reel 64 thatturns on the shaft 66 carried by the upper support 16.

Association between roving 60 and mat 65 produces the reinforcing band100 that, through the transmission rollers 23, 24 is compelled to passinto the fluid matrix of thermosetting resins 50 contained in the bath22.

On leaving said bath the band 100, guided by the rollers, is transformedinto a band 101 of plastic material incorporated into which is thereinforcing material of roving and mat.

Said band 101 enters the frame 30 that carries, on shaft 32 at its top,the reels 70 and 71 of coated copper net 72 and 73; these becomeinserted into the band 101 so producing a band 102, complete withreinforcing material and nets, which then passes through the draw bench41 pulled by the traction unit 42 with its upper and lower tracks 43 and44.

At the exit 51 from the draw bench, the band 102 is transformed into atubular shaped piece 105 which, on leaving the traction unit 42, is cutthrough by the cutter 45 turning on a pin 46.

As will be seen in FIG. 2, the nets are formed of a continuous wire 74of coated copper that forms a weft weave fabric whose successive rows,like 80 and 81, are interlaced one with another.

The wire is continuous for the whole length of the net and, as may beseen in FIG. 2 for example, starts with 75 and ends with 76 without abreak.

The enlarged illustration of some stitches shows that the wire 74 has acopper core 77 and insulating coating 78.

It follows that wherever the pultruded shape is cut, thus also cuttingthrough the nets, electrical continuity is assured for the the wholelength of nets between two cuts.

The detail in FIG. 1 shows that, at certain intervals and before entryinto the draw bench, a pair 110 of socket devices are inserted into theband 102, each device comprising a small flat plate 113 and anothersmall plate 144 with an axial channel 115 in it and sides 116.

The two plates 113 and 114 are associated together by rivets 117.

During association one end 118, 119 of the nets 72 and 73 is insertedbetween the two small plates 113, 114 of each socket device.

On the stand 47, in FIG. 1, the oblong tubular panel 106 can be seen,said panel comprising two pairs of socket devices 127, 128 and 125, 126obtained by cutting in half the socket devices 111 and 112 alreadyindicated.

FIG. 3 illustrates an area of a pultruded shaped part 105 comprisingfractions 85, 86 and 87, 88 of the nets 70 and 71, connected to thepairs 110 of socket devices already described, by terminals such as 118,119 and 120, 121.

FIG. 4 illustrates the composition of panels 106 obtained by cuttingacross the shaped part 105 at substantially half the length of the pairs110 of socket devices so that each forms two pairs of sockets 125, 126and 127, 128.

FIG. 5 shows the front of the panel 106 consisting of a narrow tubularshaped part with a rectangular cross section.

The positions of sockets 127 and 128 are clearly seen, and especiallyconnection of the wire 118 in the fraction of net 85 to the socket 127and of the wire 119 in the fraction of net 86 to the socket 128, aconnection made stable by rivets 117.

Foam plastic material 145 for heat insulation is placed inside thepanel. As seen in FIG. 5 the nets 72 and 73 can be extended to thecorners 90 by extensions 91 and 92.

It will be clear from this figure that one side 107 of the panel will behot due to transformation of current circulating in the nets 85, 86,while the side 108 will be completely cold both because of its distancefrom side 107 and because of the filling of insulating foam material 145inside the panel.

FIG. 6 shows the panel 106 with nets 85 and 86, complete with heads 130and 135.

Head 130 is formed of a bar 131 with a narrower extension 132corresponding to the internal dimensions of the panel 106.

At the centre of said head is a two-pin copper plug 133, whose arms aresized to correspond with the dimensions of the grooves 115 in thecurrent sockets 125 and 126 placed on the front of the panel.

The head 135, of substantially the same structure as head 130, presentscontacts 136 and 137 these too able to penetrate inside the grooves 115in sockets 127 and 128, said contacts being connected by wires 140 and141 to the electrical socket 142.

FIG. 7 shows panel 146 with nets 85 and 86, and with heads 150, 155.Head 150 is formed of a bar 151 with a narrower extension 152corresponding to the internal dimensions of the panel 147.

At the two ends of said head are copper contacts 153 and 154 whosedimensions correspond to those of grooves 115 in the current sockets 125and 126 placed at the sides of the panel and on its front.

The structure of head 155 is similar to that of head 150 having contacts156 and 157, these also able to penetrate inside the grooves 115 in thesockets 127 and 128, said contacts being connected by wires 160,161 tothe electric socket 162.

FIG. 8 shows a self-carrying wall 170 formed of a series of poltrudedtubular oblong panels 106 set vertically, placed side by side and joinedat two heads, an upper head 171 and a lower one 172.

Insertion of extensions 180 in the lower part of both heads inside saidpanels 106 associated side by side, helps to stabilize said associationand ensure electrical continuity between the electrically conductivenets 85, 86, generators of heat, that compose the panels and provideelectric feed.

Head 171 presents electric bridges 173 and 174 formed of copper plugs,the dimensions of whose arms correspond to the holes 115 in sockets 125and 126 incorporated into the panels 106.

The lower head 172 substantially similar to the upper head 171 presentsa pair of electric contacts 175 and 176 so placed and sized as topenetrate inside the holes 115 in the electric sockets 127 and 128 atthe other end of the panel 106.

By means of electric connections 177 and the wire 178, an electriccircuit can be closed between the various panels for regular feed fromthe main electricity supply through the plug 179.

FIG. 9 shows an oven 190 for cooking or for heat treatment to variousmaterials, formed of two side walls 191, 192, similar to the wall 170already described, a base 193 and a roof 194.

The oven is closed by doors 195 on hinges 196.

The walls 191, 192 are formed of panels 200 complete with heads 201 and202 similar to those described for the wall 170 in FIG. 8.

The panels are connected in parallel through conductors 203, 204connected to the switch 205 served by a pilot light 206.

FIG. 10 shows how the room 210 of a house can be warmed by a set 211 ofthree panels 212 substantially similar to panels 106 described above,associated by heads 221, 222 mounted on a wall 215.

The panels are electrically connected to the conductor 223 and throughthe wire 224 to the plug 225 for connection to the socket 226 and tomain electricity supply.

The applications described, such as the self-carrying wall 170 in FIG.8, the oven 190 in FIG. 9 and the series of panels 211 in FIG. 10 showonly a few examples of an infinite number of possible applications ofthe pultruded tubular bodies with a rectangular cross section,comprising the electric copper nets coated with insulating paint,generators of heat, like nets 85 and 86 already described.

What is claimed is:
 1. Process to form shaped pieces (105), bypultrusion, for transforming electric current into diffused heat, withreinforcing fibers (60, 65) and a matrix of plastic material (50),characterized in that one or more nets (72, 73) are inserted,continuously, into the plastic material (50) said nets, consisting of acontinuous wire (74) of electrically conductive material (77) coatedwith highly insulating material (78), being formed in the direction offeed of the shaped piece (105), thereby establishing electricalcontinuity from start to finish of formation of said shaped piece (105),wherein at certain intervals, devices (111, 112) for socketsincorporated in the shaped piece (105) are added to the nets forelectric current and are placed longitudinally with an internal channel(115) passing through the devices (11, 112), said channel being alignedwith the shaped piece (105) so that after said shaped piece (105) is cutthrough transversely at the position of the devices (111, 112), sockets(125-128), utilizable for connection to a source of electric current,are formed.
 2. Process as in claim 1, characterized in that the shapedpiece (105) is tubular.
 3. Process as in claim 2, characterized in thata section of the tubular shaped piece (105) is rectangular and low inheight.
 4. Process as in claim 1, characterized in that the nets (72,73) are applied to one (107) of broad surfaces (107, 108) of the shapedpiece (105).
 5. Process as in claim 1, characterized in that said one ormore nets (72, 73) laid in one or more units, on a broad surface (107)of the shaped piece (105), present extensions (91, 92) at its sides. 6.Process as in claim 1, characterized in that there are two nets (72, 73)laid side by side.
 7. Process as in claim 1, characterized in that theone or more nets (72, 73) are joined by an intermediate net ofinsulating material.
 8. Process as in claim 1, characterized in that thenets (72, 73) are made of a weft (81) woven fabric (80).
 9. Process asin claim 1, characterized in that said reinforcing fibers (60, 65) arecontinuous threads of fiberglass and/or pieces of fiberglass felt (65),wherein the one or more nets (72, 73) are added to the reinforcingmaterials,
 10. Process as in claim 1, characterized in that the matrixcomprises a thermosetting resin (50) of unsaturated polyester, epoxy, orphenolic resin.
 11. Process as In claim 1, characterized in that the oneor more nets (72, 73) are added before a resin bath.
 12. Process as inclaim 1, characterized in that the one or more nets (72, 73) are addedbefore a resins bath (50) needed for pultrusion.
 13. Process as in claim1, characterized in that the devices (111, 112) for electric socketsconsist of a first small flat plate (113) of electrically conductivematerial, said first plate (113) attached to a second small plate (114)also of electrically conductive material with an axial channel (115)open towards the first plate (113), the two plates (113, 114) beingattached to one another by rivets (117).
 14. Process as in claim 1,characterized in that foam material (145) is put into a panel (106, 147)(200, 212) to increase heat insulation so that a side (108) of the panel(106) opposite to a side (107) containing the electrically conductivenets (72, 73) remains substantially cold both because of its distancefrom said nets (72, 73) and because of the intervening foam material(145).
 15. Panels (106) obtained by the process described in claim 14,characterized in that they present means (171, 172) with which to formself-carrying walls (170), one surface (107) of the panels (106)generating heat.
 16. Process to form shaped pieces (105), by pultrusion,for transforming electric current into diffused heat, with reinforcingfibers (60, 65) and a matrix of plastic material (50), characterized inthat one or more nets (72, 73) are inserted, continuously, into theplastic material (50) said nets, consisting of a continuous wire (74) ofelectrically conductive material (77) coated with highly insulatingmaterial (78), being formed in the direction of feed of the shaped piece(105), thereby establishing electrical continuity from start to finishof formation of said shaped piece (105), wherein the one or more nets(72, 73) are placed continuously in the shaped part (105) but areseparated in lengths (85, 86) connected by pairs of devices (111, 112)for electric sockets.
 17. Process to form shaped pieces (105), bypultrusion, for transforming electric current into diffused heat, withreinforcing fibers (60, 65) and a matrix of plastic material (50),characterized in that one or more nets (72, 73) are inserted,continuously, into the plastic material (50) said nets, consisting of acontinuous wire (74) of electrically conductive material (77) coatedwith highly insulating material (78), being formed in the direction offeed of the shaped piece (105), thereby establishing electricalcontinuity from start to finish of formation of said shaped piece (105),wherein devices (111, 112) for electric sockets are inserted centrallyin the area of the shaped piece (105) to be cut through in order toobtain oblong panels (106, 147, 200, 212) so that following said cut,each device (111, 112) forms two pairs (125, 125) (127, 128) of sockets,one pair fixed to one oblong panel (106, 147, 200, 212) and the otherfixed to the next oblong panel (106, 147, 200, 212).
 18. Panels (22)obtained by the process described in claim 17, characterized in thatthey present means (201, 202) with which to form walls (191, 192) forgenerating heat in an oven (190) for cooking food or for heat treatmentof various materials.
 19. Panels (212) obtained by the process describedin claim 17, characterized in that they present means (221, 222) forforming flat bodies (211) for wall (215) or ceiling mounting, inenvironments (210) generally, the heat generating surface facing towardssaid environments.
 20. Process to form shaped pieces (105), bypultrusion, for transforming electric current into diffused heat, withreinforcing fibers (60, 65) and a matrix of plastic material (50),characterized In that one or more nets (72, 73) are inserted,continuously, into the plastic material (50) said nets, consisting of acontinuous wire (74) of electrically conductive material (77) coatedwith highly insulating material (78), being formed in the direction offeed of the shaped piece (105), thereby establishing electricalcontinuity from start to finish of formation of said shaped piece (105),wherein devices (111, 112) for electric sockets are placed on thecentral axis of symmetry of the shaped piece (105).
 21. Process to formshaped pieces (105), by pultrusion, for transforming electric currentinto diffused heat, with reinforcing fibers (60, 65) and a matrix ofplastic material (50), characterized in that one or more nets (72, 73)are inserted, continuously, into the plastic material (50) said nets,consisting of a continuous wire (74) of electrically conductive material(77) coated with highly insulating material (78), being formed in Thedirection of feed of the shaped piece (105), thereby establishingelectrical continuity from start to finish of formation of said shapedpiece (105), wherein devices (111, 112) for electric sockets are placedat sides of the shape piece (105).
 22. Process to form shaped pieces(105), by pultrusion, for transforming electric current into diffusedheat, with reinforcing fibers (60, 65) and a matrix of plastic material(50), characterized in that one or more nets (72, 73) are inserted,continuously, into the plastic material (50) said nets, consisting of acontinuous wire (74) of electrically conductive material (77) coatedwith highly insulating material (78), being formed in the direction offeed of the shaped piece (105), thereby establishing electricalcontinuity from start to finish of formation of said shaped piece (105),wherein first and second nets (72, 73) are provided and wherein devices(111, 112) for electric sockets are placed as a pair (110), the first(111) and the second (112) device in each pair (110) being respectivelyconnected to the first net (72, 73) and to the second net (72, 73). 23.Process to form shaped pieces (105), by pultrusion, for transformingelectric current into diffused heat, with reinforcing fibers (60, 65)and a matrix of plastic material (50), characterized in that one or morenets.(72, 73) are inserted, continuously, into the plastic material (50)said nets, consisting of a continuous wire (74) of electricallyconductive material (77) coated with highly insulating material (78),being formed in the direction of feed of the shaped piece (105), therebyestablishing electrical continuity from start to finish of formation ofsaid shaped piece (105), wherein at least one oblong panel (106, 147) isconnected to electric current by means of two heads (130, 135) (150,155) that can be respectively inserted at the two ends of said at leastone panel (106, 147), one head (130, 150) having two contactselectrically connected internally to the at least one panel at aposition corresponding to channels (115) in two sockets (125, 126)placed at the other end of the at least one panel (105, 147), saidcontacts being connected by wiring (140, 141), (160, 161) to a plug(142, 162) to fit into an outside socket for electric feed.